While it was so far thought that it could withstand four days, Sars-CoV-2 could actually survive for up to 28 days on smooth surfaces. This is confirmed by a new study conducted by Australian researchers from CSIRO, the results of which were published on Monday, October 12.
The shelf life of Sars-CoV-2 on materials
While studies have shown that Sars-CoV-2 can survive for up to four days on smooth surfaces, a new study is redefining the lifespan of the virus that caused the Covid-19 epidemic. Carried out by the Australian national scientific agency (Commonwealth Scientific and Industrial Research Organization), the study shows that the virus turns out to be ” extremely resistant »On smooth surfaces.
According to scientists, the virus could thus survive for up to 28 days on “ common surfaces, including banknotes, glass – like that found on phone screens – and stainless steel “. On the other hand, with regard to porous surfaces (such as cotton), the virus would survive for a shorter time: up to 14 days at the lowest temperature and less than 16 hours at the highest.
Sars-CoV-2 facing temperatures
Beyond the materials, the researchers have also shown that the lifespan of Sars-CoV-2 can vary depending on the temperatures. According to Debbie Eagles, deputy director of ACDP, the Australian health prevention center, “ At 20 degrees Celsius, which roughly matches room temperature indoors, we found the virus to be extremely hardy. […] Virus survival time decreases as temperature increases “.
To obtain this finding, the scientists subjected the coronavirus to temperatures of 20, 30 and 40 degrees. Results ? Up to 20 ° C, Sars-CoV-2 can survive for up to 28 days on glass, steel and polymer banknotes. Subjected to 30 ° C, the survival rate drops to 7 days and 24 hours when the temperature is 40 ° C.
People more contagious than surfaces
The data from the study should still be put into perspective. Indeed, the study was conducted with fixed levels of virus, probably corresponding to the peak of an infection. In other words, the particles used for the experiment had a fairly high viral load. In addition, the research was carried out in the absence of exposure to ultraviolet light, which could alter the virus.
Trevor Drew, director of the Australian Center for Disease Prevention, said the study found traces of live virus capable of infecting cell cultures. However, he insisted on emphasizing: “ it does not mean that this amount of virus could infect someone “. According to him, “ contaminated people are much more contagious than surfaces. […] It may nevertheless help explain why, even when there are no longer contagious people, the epidemic can come back even if the country is considered virus-free. “.
